| Malachite green?MG?has carcinogenicity,teratogenicity and mutagenicity to human body.In general,the most common detection methods of MG in aquatic products depend on large instruments such as HPLC and have disadvantages of fussy pre-treatment process and high detection cost.Based on this,this subject prepared molecularly imprinted polymers?MIPs?of MG by molecular imprinting technique?MIT?.The MIPs were applied to detection of MG in aquatic products as adsorbent and improved the detection accuracy and precision.In addition,the MG-MIPs were used to establish bionic enzyme linked immunosorbent assay?ELISA?detection as the bionic antibody.The method was applied to rapid detection of MG in the fish successfully with advantages of strong specificity,sensitive and accuracy.The main contents of this thesis were as follows:In chapter 1,the theory of MIT and synthesis and application of MIPs were introduced,the characteristic and preparation methods of magnetic molecularly imprinted microsphere were described concisely.And next contents were the principle and type of ELISA detection.At last,harm and detection methods of MG residue in aquatic product were summarized.In chapter 2,MIPs for MG were prepared based on emulsion polymerization and applied in pretreatment process of detection of MG in fish samples.The as-synthesized MIPs were characterized by SEM micrographs and the well shaped spherical particles with diameter distribution from 150 to 170 nm were achieved.The binding capacity of the polymers particles for MG was evaluated based on kinetic and isothermal adsorption experiments.The results showed that the adsorption equilibrium time was within 15 min for MIPs,and the maximum adsorption amounts in acetonitrile-water?20:80,v/v?were 1789?g g-1 with using for 8 times.Finally,the MIPs were successfully applied to the extraction and separation of MG in fish as a sorbent for HPLC measurement with the spiked recoveries ranging from 86.0%to 104%and the relative standard deviation less than 6%.The results indicated that the prepared MIPs exhibited excellent specific recognition for MG,which could meet requirements of pre-treatment for the determination of MG in fish samples.In chapter 3,a biomimetic direct competitive ELISA method was established for the detection of malachite green?MG?in fish samples using magnetic molecularly imprinted polymers?MMIPs?as bionic antibody.MMIPs were prepared through emulsion polymerization using Fe3O4 nanoparticles as magnetic component and characterized by the scanning electron micrographs?SEM?,thermal-gravimetric analyzer?TGA?,Fourier transform infrared spectrometer?FT-IR?and vibrating sample magnetometer?VSM?,respectively.The polymers were uniform spherical particles with the diameter was at about 600 nm.A high magnetic saturation value of 54.1 emu g-1 was obtained,which ensured the MMIPs realized magnetic separation quickly under an external magnetic field.The sensitivity of established ELISA method was 20.14?g L-1 and the detection limit was 0.12?g L-1.The selectivity experiment confirmed that the MMIPs exhibited higher selective binding capacity for MG than its structural analogues with cross-reactivity less than 7.4%.The average recovery tested by MG standard spiking was 85.0%–106%,and the relative standard deviations were less than 4.7%.The results showed that the biomimetic ELISA method was rapid,sensitive and accurate for MG analysis in fish samples.In chapter 4,MIPs films were synthesized on the surface of 96-well plates based on principle of the self-polymerization of dopamine?DA?and applied to bionics ELISA detection of MG in fish and water samples with the spiked recoveries ranging from 87.8%to 94.6%and the relative standard deviation less than 3.6%.The sensitivity of this ELISA method reached 10.31?g L-1,and the limit of detection was 0.3?g L-1.The results manifested that the ELISA method established was accurate,and it can be applied to the detection of MG in fish and water samples. |
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